need help diagnosing bad cdi or magneto

Discussion in 'Electrical' started by happyjourney, Apr 25, 2012.

  1. happyjourney

    happyjourney Member

    I am on my first build and have a wolfpack cdi. i am not getting any spark at the plug checking from turning it over and holding it neaxt to the engines fins. i can smell the gas coming thru the engine and its moving the piston. i'm wondering how to diagnose if it is the magneto that is the problem or the cdi. i haven't hooked the kill switch wires up and i know i have the wiring correct. i do have a mini gen max hooked up to the magneto but i don't see how that should effect it. i think i'm going to buy a new magneto and install that but if thats not it then send the wolfpack kit back for a replacement. i have a multimeter but i don't know what settings to put it on or which connections to check. is there a way to tell whats bad? on a side note i took the little cap off the sparkplug not thinking it needed to be the full size. i'm not sure if that is what it is but i'm going to go home and see if i can find another spark plug to take the cap from and see if it makes a difference. if it doesn't and i don't get any good advice i'm going to go buy a new magneto and go from there
     
    Last edited: Apr 25, 2012

  2. Al.Fisherman

    Al.Fisherman Active Member

    Not sure about your coil, but you can take a meter, or a 12V test light and check for output. Disconnect the generator first. Test on DCV @ 20V

    [​IMG]

    Not the red arrow/circle but where the knob is pointing (10:00 position)
     
    Last edited: Apr 25, 2012
  3. happyjourney

    happyjourney Member

    12volt test light. i think i've got one of those. is that the thing that lights up and beeps when you put it near a live electrical wire? i was reading through different posts and seem to have the impression that maybe the magneto isn't seated right as i took it out and then put it back in to put the generator on it. i'm gonna check with that setting tomorrow though and see if i can get a reading. thanks
     
  4. Big Red

    Big Red Active Member

    Magneto

    If it ain't broke, and ya mess with it long enough, it will be. I forget who's saying ( on this site) that is but it is SO true. If you had the mag off thats the first thing I would check. Take it back off. The key may have gotten pushed back behind the mag. Al came up with a great solution for this problem. Crazy glue the key in place. Then make sure the slot is lined up with the key perfectly before you try to tap it on. I've pushed many keys behind the mag so it's not just a newbie problem. If the mag ain't lined up you may not get a spark at all or a spark at the wrong time. Before you do ANYTHING else, fix what ya just fixed, only better this time.:jester:
    Big Red.
     
  5. Lunardog

    Lunardog Member

  6. Big Red

    Big Red Active Member

    Magneto

    Hey Lunardog, He just said all he's got is a test light, Maybe. If it ran before he had the magneto apart and it don't run when he reinstalled it, then I've got a pretty good idea what's wrong with it. Give the guy a chance fix what he "fixed" first. Then if he still has no spark he needs to buy a multimeter. (should have one anyway.) No spark can only be a very few things wrong. Mag, field coil, CDI or F'UP'd wiring. In this case I vote that he didn't get the mag back on right. It is possible he got a wire crossed up putting it back together but they are usually color coded. But it IS a possibility.
    Big Red.
     
  7. Al.Fisherman

    Al.Fisherman Active Member

    Piston TDC, key at 1:00...it can go on backwards.
     
    Big Red likes this.
  8. Lunardog

    Lunardog Member

    My apologies, I thought his first post stated he had a multimeter. I had to search for the info on the test reeadings and it took a while and thought it would be helpful if he needed it. Also thought the issue with no spark was before he removed the mag. Maybe I misunderstood.
     
  9. Big Red

    Big Red Active Member

    Mag

    As I understood it, He was putting on one of those "extra" field coils so he took off the original mag to make it easier. I think something went wrong then. Just trying to keep things straight bro.
    Big Red.
     
  10. Big Red

    Big Red Active Member

    Mag.

    Another great bit of information. Thanks Al.
     
  11. happyjourney

    happyjourney Member

    heres the deal. i do have a multimeter and i am getting voltage readings from the wires coming off the magneto. i am not getting readings on the wires past the electronics box that came with my cdi kit. i don't know what the key is in the magneto or how to line it up. i'll have to look that up and get that straight. i'm going to assume that having that incorrectly lined up wouldn't stop me from getting some spark. i have none. i have two other cdis that came with the shipped kits that i bought. one went through a flood and i'm sure it doesn't work, the other had the spark plug cord yanked out of it. maybe i did it before because i also have a high performance spark plug cord i bought to install into the cdi before i decided on buying the wolfpack kit. yesterday i went and bought another spark plug so i could take the cap off and screw it onto my iridium plug to see if perhaps the lkittle cap was supposed to be on to make a full connection inside of the spark plug cap. after i screwed it on figuring out that the thread patterns must not have matched it didn't fit inside the cap so i knew that it must not supposed to be on.
    i tried to unscrew the the little cap then and ended up cracking the whole tip off my brand new iridium spark plug. i'm going to order another one today. i know the problem wasn't the sparkplug because i tried installing the other one i got and got nothing for spark there either. i'm thinking that my wolfpack cdi kit must be faulty. i'm going to check there site and try and see who i have to contact to try and get a replacement.
     
  12. happyjourney

    happyjourney Member

    i'm confused about this spark plug screw on tip because on this guys site in the commonly asked questions section it says this :

    Does my spark plug need the screw-on nipple that was taken off to work with the spark cap supplied with the engine? Yes, you will need that to match the motorcycle spark cap. If you don't have one then splurge and buy an iridium tipped spark plug to give you the best performance.
     
  13. happyjourney

    happyjourney Member

    maybe i hooked the wires up backwards or have the coil upside down. is there a tutorial on moving the magneto keyhole? its hard for me to beleive this wolfpack cdi thats brand new could be defective. they also are out of stock so getting a replacement is probably going to take forever if ever.
     
  14. Lunardog

    Lunardog Member

    Again I'll state I'm a newbie here but some things seem sort of self explanitory and I'm sure the experienced guys will correct me if I'm wrong. 1) even if you had the mag keyed incorrectly if everything is functioning as it should be you would be getting spark, just at the incorrect timing. 2) you have added or adjusted so many things there are entirely too many variables to deal with my (inexperienced) suggestion would be to return everything back to base, excluding any addons like the wolfpack and then start your trouble shooting from there. No kill switch, stock mag and cdi only, check your wiring connections between mag and cdi are correct and solid (properly soldered and wrapped)verify you have a good working plug wire and new plug and that it is connected correctly and see what you have from there. Might make things easier in your troubleshooting.
     
  15. Big Red

    Big Red Active Member

    Magneto?

    Not bad advice Lunardog, Even from a newbie. If it worked before the ad on's, then it must be the ad on's. That or it just got put together different or backwards or sideways or ect. Going back to the original configuration is not a bad idea. First just get it running THEN ad parts one at a time to try to find out where things went wrong.
    Big Red.
     
    Last edited: Apr 28, 2012
  16. happyjourney

    happyjourney Member

    i found out it was the generator max thing. i tried taking the magneto off to see if i could turn it over and realized it wasn't supposed to be that way. i also reversed the wiring to see if that was it. when i removed the mini generator max thing it started getting spark at the plug when next to the fin. i also got lightly shocked from the metal housing. i still need the new spark plug with the cap on it though. i haven't heard it fire inside of the engine. i think the cap isn't making good enough contact to make it fire inside of the cylinder. that spark plug isn't made for these engines anyway. i have a new problem. i was using a dewalt drill with a socket attachment to spin the magneto via the nut on the threaded bolt and stripped it partially. can i rethread it with a cast and die set without removing the magnet? is removing and replacing that bolt close to a complete rebuild job? i also looked at the magnet for a key hole while my piston was at what looked like top dead center through the spark plug hole and saw none. maybe i didn't remove the nut and washer off far enough to see it. The middle of the mouth of one side of the magnet looked like it would have been pointing at the 2:00 position. when the clutch is disengaged and i'm coasting down the road trying to get it going with the magneto's cover off the magneto doesn't spin in a smooth manner. it only makes partial turns instead of being in cadence with the chain and drive wheel. this could be because the bolt that holds the magneto on is now stripped i'm suspecting. i need to get that remedied. what sizes are closest to that bolts size? i'm sure i'm gonna have to rethread that cause if i removed it to replace it i'm sure everything attached to it on the inside would never get lined up again screwing it back in. i had seen a post somewhere about someone say you could use a drill attachment to turn something there and get it going but they must have been talking bout the drive sprocket. oh well you live and you learn. i'll get this thing running one day, maybe.
     
  17. HeadSmess

    HeadSmess Well-Known Member

    the "bolt" is the end of the crankshaft

    slow down, take a breather, and hit enter :jester:

    firstly, "the magneto appears not too be rotating smoothly". this isnt correct. but dont blame the bolt... the magnet should be keyed rigidly to the shaft so it turns with it, allowing it to spark at the right time.

    you pulled it off and dropped the key. the key being a nasty little semicircular critter, thats hard to get in without it falling madly in love with the magnet...

    superglue it to the crank. theres a notch for it in the crank. sometimes the keys a tight fit and you can just jam it in, but normally you need to glue it. then simply line slot in magnet up with key, and slip it on :) the right way round.

    now for the stripped thread...

    stripping it involves removing the thread on it. not very good as theres only three ways to repair it... and, unless youre really good with a drill, all require pulling apart completely...

    whats a cast and die set? a TAP and die set :) you tap a hole, or run a bar through a die :)

    ok. fixing the thread. a die wont help in this case. you stripped the thread. theres no metal for a die to cut. not the right one, at least. maybe going down a size to M7 (oddball, best left alone...) or to M6. m6 would require a mounting crank in a lathe to do it nicely. turn down to 6mm and thread it again... id do it with a file, myself :) easier than pulling it all apart.

    drilling it out and tapping to m6, then using a bolt. heres where being good with the drill can help. :) otherwise, needs a lathe to be done properly. nice straight concentric hole...

    replacing the crank...

    you say "partially".... this is an ambiguous term and it may be perfectly fine if youre careful :) this would be nice :) it doesnt need to be super tight, just enough to clamp the magnet a bit... glue the nut on as well!

    its normally an M8*1 thread btw. not standard M8*1.25... leaving you m7 (weird) and m6 as viable repair options.

    and while i saw something about wires...i never saw any mention of colours of wires.

    blue goes to the cdi. black too.

    cut the white wire.get rid of it. carry a battery for electrizzity
     
    Last edited: Apr 30, 2012
  18. Big Red

    Big Red Active Member

    Stripped Out.

    Hey Happy, I did the exact same thing with the drill, AND I fubar'd the drill too. I got lucky and mostly stripped out the nut only. There was a little damage to the shaft, but I think the shaft is a harder steel than the nut.(cheap chinese nuts.) I got a new nut and it held well enough. I was afraid to tork it down REAL tight but torked it as tight as I dared.
    If I were you I would try this first. If it holds it holds.
    Big Red.
    For those that don't know, FUBAR means "F****d up beyond all recognition".
     
  19. Lunardog

    Lunardog Member

    It sounds like your getting to the point where the time and money you have in trying to repair this engine may be surpassing the cost of the engine itself. A replacement bottom end is not really that expensive nor an engine only purchase giving you a good stock of spare parts which isn't a bad thing with these things. That being said, money may be an issue for you or perhaps the enjoyment of tinkering is fun for you (like for most of us) and you just want to fix it. But I'll throw this out anyhow. Making sure that everything is lined up and installed correctly and having a shop put a few good tack welds on it. This is an absolute last resort but rather that trash the engine if that what it comes down to you may be able to use the motor untill it wears out giving you time to save and replace it. Just a thought.
     
  20. Big Red

    Big Red Active Member

    Engine

    That's what I'd do. Complete engine or just lower end replacment. Spare parts are ALWAYS a good thing.
    Big Red.
     
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